Conventionally, in order to suppress a shock from occurring in a transient state from a drive running state where an engine is driven and run with an accelerator pedal depressed for vehicle running to a coast running state with a zero accelerator opening, a device for controlling a capacity (i.e., a lock-up capacity) of a lock-up mechanism of a torque converter is generally known. For instance, a device, disclosed in Patent document 1, is configured to disable the lock-up mechanism to be engaged by reducing the lock-up capacity to a minimum capacity corresponding to a standby pressure by feed-forward control during a predetermined time period after having shifted to a coast running state.
However, in the previously-discussed prior art device, when the vehicle has shifted to a coast running state, there is a possibility that the lock-up capacity cannot be accurately controlled due to individual differences of lock-up capacity control devices manufactured.